In part 3 of “Snow White,” the newly established Fabletown in the former Castle Dark continues to yield dark secrets. Ruthless Prince Brandish locks one of Fables’ beloved princesses in a tower with no way out. And in Haven, Beast cooks up a scheme involving Geppetto and the Blue Fairy while Flycatcher enjoys a nice, relaxing bath—only to find more than a rubber duckie with him in the tub.